Mobile radio networks such as the Global System for Mobiles (GSM) and the Universal Mobile Telecommunications System ((UMTS) can provide a facility for communicating data in circuit switched mode or using data packets. In circuit switched mode a physical communications channel is allocated for a logical communications channel throughout a call. For the communication of data packets, the General Packet Radio Service (GPRS) has been developed. GPRS provides support for a packet-orientated service, which attempts to optimise network and radio resources for packet data communications such as for example Internet Packets (IP). The GPRS provides a-logical architecture, which is related to the circuit switched architecture of a mobile radio system.
The system for communicating data between a mobile communications user equipment (UE) and a packet data telecommunications network comprises: a gateway support node (GGSN) that provides an interface between the packet data telecommunications network and the user equipment for communication of data packets over the mobile telecommunications network and a service support node (SGSN) that controls communication of data packets between the gateway support node and the user equipment using a radio network controller (RNC) that controls radio resources of the telecommunications network.
The packet data is communicated either from the UE to the GGSN or from the GGSN to the UE using a single radio access bearer set up by the RNC according to a single given predetermined set of quality of service (QoS) parameters associated with the payload of the data packet. Radio resources provided by the mobile telecommunications network for communicating data packets between the UE and the RNC are a valuable commodity and can be a limiting factor in whether or not a particular radio access bearer can be supported, depending upon for example current loading of the network. As such, it is desirable to use the radio resources as efficiently as possible.